FONTANA ( — Authorities Tuesday were investigating the death of a couple and their two children who were found dead inside a Fontana home.

Officials received a call from a 16-year-old boy related to one of the victims around 8:30 p.m. Monday saying his family members had been injured or killed at a residence in the 7300 block of Palmetto Avenue.

The police responded and discovered the bodies, identified by the San Bernardino County Coroner as 38 year-old Ramon Miranda, 34 year-old Silvia Miranda, 10 year-old Rayna Miranda and 12 year-old Ramon Miranda Jr.

According to detectives, the two children and adult female suffered multiple gunshot wounds and the adult male had a single gunshot wound to the head.

Investigators recovered a handgun inside the home and say they believe it was a case of domestic violence. Authorities say they are not looking for a suspect and believe it was a murder-suicide. The motive has not been confirmed.

Neighbors reported hearing loud arguing coming from the house Monday night before police were called.

“A couple arguing before like earlier before any of this happened, so then like everybody was out here. Some man was running up and down the streets,” resident Jessica Aranz said.

Police say there is no record of domestic violence at the home.

Investigators are awaiting results of the autopsies next week.

Fontana Mayor Acquanetta Warren said on Tuesday the community is grieving.

“As a community we are standing together to support this family and keeping them in our prayers,” she said. “On behalf of the Mayor and Council we offer our condolences to the family.  We are grieving with them.”